cmux

A Ghostty-based macOS terminal with vertical tabs and notifications for AI coding agents.

Date Created:

February 12, 2026

Platform:

macos

Language:

swift

Source Code Availability:

Open Source (GPL-3)

Development State:

active

cmux is a native macOS terminal with a built in multiplexer based on libghostty, the engine behind the Ghostty terminal.

It's made for running AI coding agents like Claude Code, Codex, OpenCode and Gemini CLI in parallel, each in its own pane.

A sidebar of vertical tabs shows what each workspace is doing, and cmux nudges you with pane rings, badges and native macOS notifications when an agent needs you. A built-in browser pane even lets agents click around without leaving the terminal.

Features

GPU Accelerated

Yes

Image Support

Yes

Sixel

No

Kitty Graphics

Yes

iTerm2 Images

No

3D Mode

No

Inline 3D

No

Ratty Graphics Protocol

No

Glyph Protocol

No

True Color (24-bit)

Yes

Font Ligatures

Yes

Tabs

Yes

Split Panes

Yes

OSC 52 Clipboard

Yes

OSC 8 Hyperlinks

Yes

Unicode

Yes

Notifications

Yes

Kitty Keyboard

Yes

Synchronized Output

Yes

Styled Underlines

Yes

Shell Integration

Yes

Drop-down Mode

No

Built-in Multiplexer

Yes

Config Format

JSON

How to install cmux

As cmux is available only on macOS, you can install cmux via brew (brew install cmux) or you can download it manually via the website or via their releases page.

Compare cmux With:

Alacritty

Ghostty

iTerm2

Kitty

Terminal.app

Warp Terminal

Wave Terminal

Wezterm